Brake-slack take-up.



Patented Nov, l4, I899.

I J. c. WANDS. BRAKE SLACK TAKE-UP.

(Application filed Mar. 25, 1898.)

3 ShaetsSheet I.

No Model.)

Patented Nov. I4, [899.

J. C. WANDS.

BRAKE SLACK TAKE-UP.

(Application filed Mar. 25, 1898.)

3 Sheets-$heet 2,

(No Model.)

'n-l: NORRIS PETERS co. momuma. WASHINGTON, n. c,

UNIT D STATES PATENT OFFICE.

JOHN C. WANDS, OF ST. LOUIS, MISSOURI.

BRAKE-SLACK TAKE-UP.

SPECIFICATION forming part of Letters Patent No. 636,874, dated November14, 1899.

Application filed March 25, 1898- To all whom it may concern.-

Be it known that I, JOHN C. WAN'Ds, a citizen of the United States,residing at St. Louis, in the State of Missouri, have invented certainnew and useful Improvements in Air- Brake Controllers; and I herebydeclare the following to be a full, clear, and exact description of thesame, reference being had to the accompanying drawings, in which- Figure1 is a plan view of devices embodying my invention as applied inconnection with an air-brake cylinder and the levers of a brake-rigging.Fig. 2 is a side elevation thereof. Fig. 3 is a detached view of thetierod with turnbuckle-sheave in section and portions of the clevises orjaws which connect the tie-rod with the levers. Fig. 4 is an end view ofthe turnbuckle-sheave, partly in section, and the bridle-sheaves. Fig. 5is an enlarged side View of a clevis or jaw and portion of a tie-rod, asshown in Fig. 1. Fig. 6 is a longitudinal section of the clevis or jawon the line 6 6, Fig. 5. Fig. 7 is a transverse section on the line 7 7,Fig. 5. Figs. 8, 9, and 10 are views in elevation and section of onemodification in the construction of clevis and tie-rod. Figs. 11, 12,and 13 are views in elevation and section of another modification in theconstructionof clevis and tie-rod; and Figs. 14, 15, and 1 6 areenlarged detail views in elevation and in section, showing a simplifiedconstruction of the clevis and tie-rod connection.

Like symbols refer to like parts wherever they occur.

My invention relates to that class of devices which may be termedair-brake controllers, inasmuch as they have for their function theautomatic elimination of slack from the brake system, thus limiting andcontrolling the working stroke of the air-brake piston.

As is well understood by those skilled in the art, any slack or lostmotion in the brakerigging arising from wear of the brake-shoes or othercause is multiplied by the lever system, sothat a greatly-increasedmovement of the air-brakepistonis required to apply the brakes, and saidincreased movement of the piston is not only attended with proportionateloss of power, but in case the movement is excessive the piston of theair-cylinder may Serial No. 675,201. (No model.)

bottom in the cylinder before the brakes are effectively applied.

As generally constructed this class of devices commonly depend onutilizing the excessive movement of some portion of the brake-rigging toactuate the mechanism whereby the slack is eliminated from the system;but I prefer to actuate the slack-eliminating mechanism directly fromthe piston-rod of the air-brake, and in carrying out my invention Icombine or connect the piston-rod 'of the air-brake cylinder and thetie-rod of the brake system by means of a bridle, means for retractingthe same, and an interposed turnbuckle.

. The main feature of my present invention embraces the combination,with said bridle and means for retracting the same, of a turnbucklecomposed of a tie-rod having thread ed ends and clevises threaded toreceive the threaded ends of the tie-rod,whereby a stiifer and strongerconnection between the brakelevers is secured and cross strains andvibration of the tie-rod are lessened.

A second feature of the invention embraces the combination, with thetie-rod, of a turnbuckle-sheave, said tie-rod having threaded ends,clevises having nut-cavities, and inserted nuts adapted to receive thethreaded ends of the tie-rod and provided with means for preventing therotation of the nut in the barrel of the clevis, whereby the wear in theturnbuckle may be reduced to a minimum and repair thereof greatlyfacilitated.

There are other minor features of invention, all as will hereinaftermore fullyappear.

I will now proceed to describe my invention more fully, so that othersskilled in the art to which it appertains may apply the same.

In the drawings, A indicates an air-brake cylinder, (in the presentinstance such as is used on passenger-coaches,) a the piston-rodthereof, and B B levers of a brake system, one of said levers B beingpivotally connected at one end with the piston-rod a and the otherpivoted at one end to the head of cylin der A or other fixed point, asthe case may be, while to the opposite ends of said levers B B areattached the pull-rods b b.

0 indicates the tie-rod, (or fulcrumrod,) which connects the two leversBB, and G the turnbucklesheave journaled thereon. This ICO tie-rod iscomposed of the main or rod section 0, threaded right and left at itsends, as at c c, and the clevis or jaw sections C O, which are pivotallyconnected with the respective levers B B, the bores of said clevises O 0being provided internally with nuts 0 for the reception of the threadedends of the rod-section and at their outer ends with smoothguide-orifices c of substantially the diameter of the unthreaded portionof the tie-rod C, so as to embrace the tie-rod, obviate vibration, andrelieve the threaded portions of the tierod of cross-bending andbreaking strains incident to the vibration due to the location and useof the tie-rod or fulcrum-rod C.

Where simplicity is desired, the nut 0 may be formed integral with thejaw, as indicated in Figs. 14, 15, and 16 of the drawings; but as insuch case the nut must be of the same material-and maleable-iron castingis most desirable for the clevis or jaw, while such material is not sodesirable for the nut-I prefer to make the nut separable from the clevisand of such shape as will prevent its rotation when inserted in the boreof the jaw or clevis, which may be accomplished in various ways. InFigs. 8, 9, and 10 of the drawings this is accomplished by forming thenut polygonal or with parallel sides and the nut-seat of correspondingform, the nut being introduced into the bore of the clevis through aside opening, which may be subsequently closed and cemented, as at d, toprevent the entrance of dust, dirt, and moisture, or, if preferred, thenut 0 may be of less diameter than the bore (see Figs. 11, 12, and 13)through which it is introduced, being prevented from rotation by meansof lugs or projections 0011 the interior of the clevis, which entercorresponding indentations in the nut 0 the bore being closed after theintroduction of the nut by a screw sleeve or cap f, in the end of whichthe guideorifice c is formed for the passage of the tierod 0.

As shown in Figs. 1 to 7, inclusive, the clevis or jawis made of lateralseparable sections having on their interior pointed lugs c, which engagein corresponding indentations in the periphery of the nut 0 the lateralseparable sections being held together by the ring or collar, which isforced into position, and, if desired, by a suitable bolt or rivet d.

Keyed or otherwise firmly attached to the tie-rod C at or about itsmiddle is a ratchetring 9, and journaled loosely thereon is theturnbuckle-sheave G, composed of separable sections adapted to incloscthe pawl or dog g, which engages the ratchet-ring g on the tierod 0.

D indicates a flexible connection or bridle connected at one end to thepiston-rod a of' where its opposite or free end is connected with aspiral or other suitable spring or equivalent means of applying tensionto the free end of the bridle. The length of bridle D from the point ofits attachment to the piston-rod a to its point of attachment to theturnbucklesheave G is such as will provide sufficient slack for thenormal travel of piston-rod a, and from the point of its attachment tothe turnbuckle-sheave G to the point of its attachment to the springwithin spring-box or casing E its length is such that the spring will beat the limit of its expansion when the turnbuckle-sheave is at rest.

The controller devices being constructed substantially as hereinbeforespecified will operate as follows: Until such time as the wear on thebrake-shoes or other causes produce an increase of slack or lost motionin the brake-rigging the travel of the air-brake piston will of coursebe normal and only take up the provided slack in the bridle D, and theturnbuckle-sheave G will remain stationary; but so soon as increasedslack occurs in the system the slack in the bridle D will not besufficient to accommodate the excessive travel of the piston necessaryto take up the lost motion in the brake system. Consequently the drafton the bridle will cause the rotation of the turnbuckle-sheave G, whichmotion, however, will only cause the travel of the dog or pawl 9 overthe ratchet-ring 9 without causing the rotation of the tie-rod C. When,however, the brakes are taken off or upon the inward travel of thepiston-rod a, the bridle will be allowed to slacken, and the reaction ofthe spring in casing c, which has through the means of the bridle D beencompressed by the rotation of turnbuckle-sheave G, will cause thereverse rotation of turnbucklesheave G, which, acting through pawl g onratchet-ring 9, will cause the rotation of the tie-rod 0. As theclevises or jaws G C are connected to the levers B B, and thereforecannot rotate, the rotation of the rod acting through the right and lefthand threads will cause the jaw or clevis sections to travel toward eachother or inward on the tie-rod C, thus shortening the connection andeliminating the lost motion or slack from the system, so that the nextoutward travel of the pistonrod will not exceed its normal movement.

Having thus described myinvention, What I claim, and desire to secure byLetters Patcut, is-

1. The combination with an air-brake cylinder and its piston, of leversone of which is connected with the piston of the air-brake cylinder andwith a pull-rod, a tie orfulcrum rod comprising internally-threadedclevises connected with the levers and an intermediate rod threaded atits ends, pawl-and-ratchet devices mounted on the tie-rod, means foractuating the pawl-and-ratchet devices from the piston of the air-brakecylinder, and means for reversing the movement of the pawl-andselec /4g;

ratchet devices when released by the airbrake piston; substantially asand for the purposes specified.

2. In a tie-rod, the combination with clevissections composed ofseparable sections, of a separable inserted nut for each section,rneansfor preventing the rotation of the nuts, and an intermediate rodreversely threaded at its ends, substantially as and for the purposesspecified.

3. In a tie-rod, the combination of an intermediate rod-section,tubu1arclevises arranged to swivel on said rod-seotion, one of said cleviseshaving a nut within its bore, the rod threaded at its end to engage saidnut, a 15 sheave journaled on said rod-section, and means whereby thesheave rotates the rod in one direction, substantially as and for thepurposes specified.

In testimony whereof I affix my signature, 20 in presence of twowitnesses, this 12th day of

